1. Field of the Invention
The present invention relates generally to systems that effect hair removal, also termed epilation or depilation. More particularly, the invention relates to apparatus that provide for permanent hair removal by photo-thermal depilation techniques.
2. Description of the Prior Art
Permanent hair removal can be realized by several known techniques, including electrolysis and photo-thermal depilation. Each of these methods involves the destruction of a nutrient providing area at the base of the follicle. This area, which may be termed the xe2x80x98growth support tissuexe2x80x99 of the follicle is the papilla, which is supplied with nutrients by capillary blood vessels. It is well known in the art that simply (physically) removing a hair will not prevent another from growing in its place. To achieve permanent hair removal the growth support tissue at the base of the follicle must be destroyed.
Traditional electrolysis employs a technique wherein a needle is inserted into the sub-dermal follicle region. The needle serves as an electrode from which an electric current emanates to coagulate and destroy the growth support tissue (of a selected follicle). However, traditional electrolysis is considered to have associated with it several undesirable characteristics. First, the actual effectiveness of electrolysis is greatly determined by the skill of the operator and the proper placement of the needle within the follicle. A person undergoing such a procedure will experience some discomfort, even when topical anesthetic lotions are applied. In addition, it is not uncommon for an individual to experience redness and possibly tenderness in a treated area for a period of time following a treatment session.
In situations where the operator""s traditional electrolysis skill was marginal, permanent hair removal may not be efficiently realized, with follow up treatment sessions required to re-treat the same area. Finally, for individuals who have an aversion to needles and needle-based devices, this method of depilation can be quite unattractive.
A subsequent technique was developed that delivers energy to the base of the follicle by employing a high energy light pulse. Thus, photo-coagulation is accomplished by delivering pulsed light energy of a sufficient energy level, having a sufficiently short duration. If the (light) energy is delivered to the follicle over too long a period of time, a xe2x80x98self-coolingxe2x80x99 ability of the epidermis results in an incomplete photo-coagulation, and permanent hair removal may not result. This process is greatly preferred over traditional electrolysis, especially if-a needle-less probe is used to deliver the light pulse to the follicle. Also, when a light pulse is properly delivered to a selected follicle having a proper energy level, for a sufficiently short duration, painless, irritation free depilation results.
Previous photo-thermal depilation systems have proven that a high energy xenon flash lamp may be employed to produce a light energy pulse capable of causing photo-thermal coagulation at the base of the follicle. However, controlling and maintaining the light pulse intensity and or light pulse duration over an extended period of time has proven difficult, especially as the flash lamp ages. Other common problems involved providing a pulse of a sufficiently short duration, and efficiently delivering the light pulse to a selected follicle. In particular, prior art systems have not provided efficient and reliable arrangements to deliver a high energy light pulse produced by a flash lamp to a selected follicle to effect the desired photo-thermal depilation. As a result, such systems employed xenon flash lamps that produced light pulses having significantly greater energy levels than actually required (essentially due to their inefficient optical delivery structures and their simple and inefficient power supplying means).
Other known systems, such as that disclosed by the utility U.S. Pat. No. 3,693,623 to Harte et al., required a narrow and hollow needle-type probe having a diameter of 125 to 200 microns, which required the operator to insert the probe into the upper follicle region. As with traditional electrolysis, operator skill again becomes a critical consideration for such a system. Further, as discussed above, when a light pulse produced is of too long a (temporal) duration, epidermal self cooling results. In such cases, additional optical energy must be provided, to cause the desired photo-thermal depilation. This additional energy may also result in discomfort to the patience/client receiving the depilation treatment. Finally, known prior art systems do not provide any means to conveniently calibrate or set the intensity level of the high energy light pulse to a desired level. This type of self-calibration capability is most desirable to provide safe, consistent, and effective photo-depilation over a long period of time.
Therefore, there is a need to provide new and improved apparatus to provide reliable, safe, and consistent photo-thermal depilation to effect permanent hair removal. Embodiments of the present invention may be provided incorporating one or more of the following capabilities, features, characteristics, and or advantages:
an xe2x80x98energy supplying arrangementxe2x80x99 to deliver a shaped current pulse having an appropriate duration to energize a suitable flash lamp (e.g., a xenon flash lamp);
a charged delay line provided as a component of the energy supplying arrangement;
an optical light guide having a diameter of 2 to 4 milli-meters into which a high energy light pulse is efficiently coupled from a suitable flash lamp;
a needle-less tapered probe having a simple construction that is provided at an output end of the optical light guide;
the tapered probe specifically structured to receive the light pulse and efficiently concentrate the light pulse to a diameter of approximately 0.5 milli-meters, for delivery to a selected hair follicle;
preferably delivers approximately 5 to 15 joules per square centimeter of energy that may be applied to the hair follicle at the epidermal level (no need to penetrate the skin with a needle-type probe);
a calibration portal to receive the output end of the tapered probe to enable an operator to calibrate the intensity (or energy) level of the light pulse delivered each time the flash lamp is triggered;
a control means (e.g., an embedded computer) to periodically trigger the flash lamp at a pre-determined rate, for a pre-determined length of time (i.e., session);
a user interface to enable a user or operator to establish at least one of the pre-determined rate and the pre-determined length of time for a respective session;
embodiments wherein an external computer is employed for collecting session and billing information, enabling remote monitoring of the photo-thermal epilation system""s operation and usage, providing for the remote billing and or remote credit allocation, supporting remote maintenance monitoring, accumulating client data, assisting in performing operational analysis, providing intelligent operator guidance and assistance, performing operator training, monitoring, and evaluation, monitoring compliance with standard operational requirements, etc.; and
generally economical and reliable construction using a number of proven off-the-shelf components.
The above listed items, capabilities, characteristics, features, and or associated novel features of the presently described invention, as well as others, will become clear from a careful review of the description and figures provided herein. Attention is called to the fact, however, that the drawings and descriptions included herewith are illustrative only. Variations are contemplated as being part of the invention, limited only by the scope of the appended claims.
In accordance with the invention, a photo-thermal epilation apparatus is provided that is employable to effect permanent hair removal. The desired-permanent hair removal is realized by delivering a high energy light pulse of a sufficiently short duration to effect photo-thermal coagulation of growth support tissue of a selected hair follicle. The apparatus includes a flash lamp having an energy input coupling and provisions for triggering. A power supply module is configured with an output that is capable of providing suitable energy to charge an energy storage module (during an interval between each light pulse produced by the flash lamp). The energy storage module is coupled to the output of the power supply module, and arranged to collect and store energy supplied by the power supply module to enable the flash lamp to be properly energized when triggered. The energy storage module, which is configured with an output having a characteristic impedance matched to the input impedance of the flash lamp, is structured to deliver a flattened and extended current pulse that is coupled to the energy input coupling of the flash lamp to energize the flash lamp in order to produce the high energy light pulse.
An optical system is further included to efficiently receive the light pulse produced by the flash lamp and deliver the light pulse to a selected hair follicle to effect the desired photo-thermal depilation of growth support tissue thereat. An optical light guide is provided having a first input end and a second output end. An optical coupler is structured to efficiently couple the light pulse produced by the flash lamp into the first input end of the optical light guide. The light pulse then travels along the optical light guide and is delivered to the second end (of the optical light guide). A tapered needle-less probe is provided at the second end of-the optical light guide and arranged to receive and deliver the light pulse to the selected hair follicle. The tapered probe is configured with an optical light guide portion structured to narrow and concentrate the light pulse before delivery to the growth support tissue of the selected hair follicle. The light pulse is narrowed and concentrated to provide a sufficient energy density to cause the desired photo-thermal coagulation.
A preferred embodiment of the energy storage module includes a charged delay line for energy storage and waveshaping purposes. When the flash lamp is-triggered, a current pulse is produced at the output of the energy storage module, and received by the flash lamp to produce the high energy light pulse. In a most preferred embodiment, the energy storage module includes a plurality of capacitors and a plurality of inductors arranged in a series-parallel configuration. The plurality of discrete inductors are arranged in a cascade, with each inductor having an input terminal and an output terminal. Each respective capacitor is connected between the output terminal of each inductor and a common reference (or return) node, thus forming the series-parallel configuration.